Data transmission system, data transmission apparatus and data transmission method thereof

ABSTRACT

A data transmission apparatus includes: a first port and a second port which are selected by a first control signal; a first signal path and a second signal path which are selected by a second control signal. When a memory card satisfies a first condition, the first control signal selects the first port and the second control signal selects the first signal path, the data transmission apparatus connects the host device and the memory card via the first port and the first signal path and works in a first transmission mode. When the memory card satisfies a second condition, the first control signal selects the second port and the second control signal selects the second signal path, the data transmission apparatus connects the host device and the memory card via the second port and the second signal path and works in a second transmission mode.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to and the benefit of Chinese PatentApplication No. CN202110246450.9, filed on Mar. 5, 2021. The disclosureof the above application is incorporated herein by reference.

FIELD

The present disclosure relates to the technical field of datatransmission, especially to a data transmission system, a datatransmission apparatus, and a data transmission method.

BACKGROUND

The statements in this section merely provide background informationrelated to the present disclosure and may not constitute prior art.

With the development of science and technology, many electronic devicesare used in our lives and data processing increases accordingly.Therefore, external memory cards are used frequently. In this condition,data information is stored in external memory cards, users can read orwrite data from or into the external memory card, for example, SD card.SD cards are in constant updating process to improve transmission speed,and different types of memory cards have different transfer protocols.So, the electronic device can adapt to all kinds of SD card and works inthe best transfer rate is necessary. For example, the normal SD cardworks in normal transmission mode and the high-speed SD card works inhigh-speed transmission mode.

FIG. 1 shows a conventional data transmission system 100. The datatransmission apparatus 110 provides communication between normal SD cardand/or high-speed SD card and host device 102. As shown in FIG. 1, thedata transmission apparatus 110 includes a PCIE switch 1002 and atransfer controller 1006. Wherein the PCIE switch 1002 includes aPCIE-PHY1, a PCIE-PHY2, a PCIE-PHY3 and an analysis module 1004.Specifically, when the memory card 104 supports normal transmissionmode, e.g. SD3.X-SD.6.X, the analysis module 1004 determines thetransmission mode of the memory card 104 by analyzing a data packet sentfrom the host device 102. If the memory card 104 are SD3.X-SD.6.X whichsupport normal transmission mode, the analysis module 1004 selects thesignal path between the PCIE switch 1002 and the transfer controller1006 according to physical layer PCIE-PHY1 for performing communicationbetween the host device 102 and the memory card 104. On the contrary, ifthe memory card 104 is SD7.X which supports high-speed transmissionmode, the analysis module 1004 selects the signal path between the PCIEswitch 1002 and the transfer controller 1006 according to physical layerPCIE-PHY2 for performing communication between the host device 102 andthe memory card 104. The PCIE switch in FIG. 1 is very expensive and hasa complex circuit design. So, a data transmission apparatus which savesPCIE switch when providing communication between the host device and thememory card of all kinds of type is necessary.

FIG. 2 shows another conventional data transmission system 200 whichsolves the shortcomings of the highly expensive PCIE switch in FIG. 1.As shown in FIG. 2, the data transmission apparatus 210 includes aPCIE-PHY 202, a transfer controller 204, and a signal selecting module206. The signal selecting module 206 is configured to receive a levelfrom a memory card 104 to determine the type of the memory card 104; forexample, the memory card supports normal transmission mode or high-speedtransmission mode. Specifically, the memory card 104 which supportsnormal transmission mode will return a low level to the datatransmission apparatus 210, while the memory card 104 which supportshigh-speed transmission mode will return a high level to the datatransmission apparatus 210. The signal selecting module 206 determinesthe type of the memory card 104 according to the level sent from thememory card 104. When the memory card 104 supports normal transmissionmode, the signal selecting module 206 connects with the host device 102via the transfer controller 204 and the PCIE-PHY 202. Otherwise, thesignal selecting module 206 connects with the host device 102 directly.As described in FIG. 2, the data transmission apparatus 210 needs atleast two signal paths to connect with two interfaces of the host device102, wherein each signal path (PCIE bus) includes PCIE root complex, thetwo signal paths connect with two PCIE root complexes in the host device102. However, the number of PCIE interfaces in the host device 102 usedto connect external devices is limited, so saving PCIE interfaces isimportant.

More important, there are some other shortcomings disclosed in prior artas above. If the memory card 104 is SD4.X-SD6.X that supports UHSIImode, the host device 102 communicates with the memory card 104 in UHSImode, as the host device 102 cannot identify if the memory card 104supports USHII mode. To solve this problem, the data transmissionapparatus disclosed below can support high-speed transmission mode,normal transmission mode which includes USHII mode and USHI mode.According to the data transmission apparatus in this invention, the datatransmission apparatus performs different transmission mode fordifferent types of the memory card which does not increase PCIE switchand saves PCIE interfaces too.

SUMMARY

This section provides a general summary of the disclosure and is not acomprehensive disclosure of its full scope or all of its features.

Disclosed are embodiments of a data transmission apparatus providingcommunication between a memory card and a host device. The datatransmission apparatus comprises: a first port connects to a controlmodule in the data transmission apparatus, is selected by a firstcontrol signal; a second port connects a card signal selecting module inthe data transmission apparatus, is selected by the first controlsignal; a first signal path connects to the control module and the cardsignal selecting module, the data transmission apparatus implementssignal transmission between the control module to the card signalselecting module by the first path, wherein a second control signal isused to select the first signal path; and a second signal path connectsto the host device and the card signal selecting module, the host devicetransmits signal to the card signal selecting module by the secondsignal path, wherein the second control signal is used to select thesecond signal path, when the memory card satisfies the first condition,the first control signal selects the first port and the second controlsignal selects the first signal path, the data transmission apparatusconnects the host device and the memory card via the first port and thefirst signal path, and works in a first transmission mode, when thememory card satisfies the second condition, the first control signalselects the second port and the second control signal selects the secondsignal path, the data transmission apparatus connects the host deviceand the memory card via the second port and the second signal path, andworks in a second transmission mode.

In other embodiments, a data transmission method for providingcommunication between a host device and a memory card is provided. Thedata transmission method comprises: a data transmission apparatusgenerating a first control signal to make the host device connect to thedata transmission apparatus; wherein the data transmission apparatusgenerates a second control signal to make the data transmissionapparatus connect to the memory card; when the memory card satisfies thefirst condition, the first control signal selects a first port and thesecond control signal selects a first signal path, the data transmissionapparatus connects the host device and the memory card via the firstport and the first signal path, and works in a first transmission mode,when the memory card satisfies the second condition, the first controlsignal selects a second port and the second control signal selects thesecond signal path, the data transmission apparatus connects the hostdevice and the memory card via the second port and the second signalpath, and works in a second transmission mode.

In another embodiment, a data transmission system which includes a hostdevice, a data transmission apparatus and a memory card is provided. Thedata transmission system includes: a first control signal configured tocontrol a signal path between the host device and the data transmissionapparatus; a second control signal configured to control another signalpath between the data transmission apparatus and the memory card; whenthe memory card satisfies the first condition, the first control signalselects a first port and the second control signal selects a firstsignal path, the data transmission apparatus connects the host deviceand the memory card via the first port and the first signal path, andworks in a first transmission mode, when the memory card satisfies thesecond condition, the first control signal selects a second port and thesecond control signal selects a second signal path, the datatransmission apparatus connects the host device and the memory card viathe second port and the second signal path, and works in a secondtransmission mode.

In another embodiment, a method for switching signal path in a datatransmission system is provided. When the memory card is removed fromthe data transmission system, the method for switching signal pathincludes: a data transmission apparatus keeps selecting a first port ifthe memory card which is removed satisfies a first condition, and a hostdevice connects with a control module in the data transmissionapparatus; and the data transmission apparatus keeps selecting a secondport if the memory card which is removed satisfies a second condition,and will break connection with the second port after a period of time,and then selects the first port.

Further areas of applicability will become apparent from the descriptionprovided herein. It should be understood that the description andspecific examples are intended for purposes of illustration only and arenot intended to limit the scope of the present disclosure.

DRAWINGS

The features and advantages of embodiments of the claimed subject matterwill become apparent as the following detailed description proceeds, andupon reference to the drawings, where like numerals depict like parts,and in which:

FIG. 1 shows a conventional data transmission system 100.

FIG. 2 shows another conventional data transmission system 200.

FIG. 3 shows an example of a data transmission system 300 which includesa host device, a data transmission apparatus and a memory card, inaccordance with an embodiment of the present invention.

FIG. 4 shows an example of another data transmission system 400 whichincludes a host device, a data transmission apparatus and a memory card,in accordance with an embodiment of the present invention.

FIG. 5 shows an example of a mode selection and switch module 306 in thedata transmission apparatus 310 shown in FIG. 3, in accordance with anembodiment of the present invention.

FIG. 6 shows a flowchart of an example of a data transmission method forproviding communication between a host device and a memory card, inaccordance with an embodiment of the present invention.

FIG. 7 shows another flowchart of an example of a data transmissionmethod for providing communication between a host device and a memorycard, in accordance with an embodiment of the present invention.

FIG. 8 shows another flowchart of an example of a data transmissionmethod for providing communication between a host device and a memorycard, in accordance with an embodiment of the present invention.

FIG. 9 shows a flowchart of an example of a method for switching signalpath, in accordance with an embodiment of the present invention.

The drawings described herein are for illustration purposes only and arenot intended to limit the scope of the present disclosure in any way.

DETAILED DESCRIPTION

The following description is merely exemplary in nature and is notintended to limit the present disclosure, application, or uses. Itshould be understood that throughout the drawings, correspondingreference numerals indicate like or corresponding parts and features.

Reference will now be made in detail to the embodiments of the presentinvention. While the invention will be described in combination withthese embodiments, it will be understood that they are not intended tolimit the invention to these embodiments. On the contrary, the inventionis intended to cover alternatives, modifications and equivalents, whichmay be included within the spirit and scope of the invention as definedby the appended claims.

Furthermore, in the following detailed description of the presentinvention, numerous specific details are set forth in order to provide athorough understanding of the present invention. However, it will berecognized by one of ordinary skill in the art that the presentinvention may be practiced without these specific details. In otherinstances, well-known methods, procedures, components, and circuits havenot been described in detail to avoid obscuring aspects of the presentinvention.

FIG. 3 shows an example of a data transmission system 300 which includesa host device 102, a data transmission apparatus 310 and a memory card104, in accordance with an embodiment of the present invention. As shownin FIG. 3, the data transmission system 300 includes a host device 102,a data transmission apparatus 310 and memory card 104. The host devicecan be, but is not limited to, a host in an electronic device capable ofreading data from or writing data to the memory card. By way of example,the electronic device may be a MacBook, PC, digital camcorder, IPAD etc.The data transmission apparatus 310 includes an analog signal switchmodule 3021, an analog signal switch module 3022, a control module 304,a mode selection and switch module 306 and a card signal selectingmodule 308. The memory card 104 can be, but is not limited to, memorycard SD3.X-SD7.X, wherein the memory card SD3.X-SD6.X supports normaltransmission mode. In another word, the host device 102 communicateswith the memory card 104 via the data transmission apparatus 310 in anormal transmission mode which includes UHSI (Ultra High Speed I) modeand UHSII (Ultra High Speed II) mode. UHSI mode and UHSII mode are bothnamed as normal transmission mode as below. Specifically, the datatransmission apparatus 310 communicates with the memory card SD3.X inUHSI mode and communicates with the memory card SD4.X-SD6.X in UHSIImode. However, the data transmission apparatus 310 communicates with thememory card SD7.X in a High-speed transmission mode. In the presentapplication, the data transmission apparatus 310 switches transmissionmode between normal transmission mode and high-speed transmission modeaccording to the type of the memory card 104 and takes full advantage ofthe ability of the memory card 104.

The data transmission apparatus 310 in accordance with an embodiment ofthe present invention can be used as a data transmission chip in acomputer and provides communication between the computer and externalmemory card. The data transmission chip can be a card read controller.The data transmission apparatus 310 can be used in any electronicequipment that needs data transmission, for example: digital camcorder,mobile phone, computer, etc.

The host device 102 includes SD card slot which is an interface betweenthe host device 102 and the memory card 104. The pins of the SD cardconnect with pins of the SD card slot and performs data transmission.

As shown in FIG. 3, the analog signal switch module 3021 connects withthe host device 102 via a signal path 321. The signal path 321 can bePCIE (peripheral component interconnect express) bus. In one embodiment,the analog signal switch module 3021 is a high-speed multiplexer (MUX).It should be understood by the person having ordinary skill in the artthat the analog signal switch module 3021 can be another device whichcan perform the function of MUX. The analog signal switch module 3021connects with the control module 304 via the signal path 3005, and thecard signal selecting module 308 selects signal path 3009 to communicatewith the mode selection and switch module 306 when the memory card 104supports the normal transmission mode. The data transmission apparatus310 works in a first transmission mode when the memory card supportsnormal transmission mode. The analog signal switch module 3021 selectssignal path 3001 to connect with the card signal selecting module 308,the analog signal switch module 3021 connects with the analog signalswitch module 3022 via signal path 3011, and the analog signal switchmodule 3022 connects with the memory card 104 via signal path 3223 whenthe memory card supports high-speed transmission mode, wherein theanalog signal switch module 3021 and the analog signal switch module3022 are both the same MUX module. The data transmission apparatus 310works in a second transmission mode when the memory card supportshigh-speed transmission mode. In one embodiment, the card signalselecting module 308 which is a low-speed MUX connects to the memorycard 104 via signal path 3221, is configured to switch on signal path3001 or signal path 3009.

Specifically, the level of the response signal from memory card 104 ishigh level when the memory card 104 supports normal transmission mode,it is also called that the memory card 104 satisfies a first condition.On the other hand, the level of the response signal from memory card 104is low level when the memory card 104 supports high-speed transmissionmode, it is also called that the memory card 104 satisfies a secondcondition. Wherein the response signal sent from the memory card 104 istriggered by a command signal sent from a control module 304, it will bedescribed in FIG. 4 as below.

As disclosed above, the data transmission apparatus 310 providescommunication between the host device 102 and different types of memorycard 104, in accordance with an embodiment of the present invention. Thecard signal selecting module 308, the analog signal switch modules 3021and 3022 select corresponding signal paths to transmit data which solvesthe problem of high cost of PCIE switch in conventional technology andsolves the problem of using two PCIE paths. The data transmissionapparatus 310 improves transmission efficiency and decreases the cost ofproviding communication between host device and memory card accordingly.

FIG. 4 shows an example of another data transmission system 400 whichincludes a host device 102, a data transmission apparatus 310 and amemory card 104, in accordance with an embodiment of the presentinvention. The signals shown in FIG. 4 will be described as below whichincludes the name and function information.

No. Name Description 1 PERSET# is used to reset memory card, and definedby PCIE 2 PCIE TX± PCIE TX± signal, send differential output 3 PCIE RX±PCIE RX± signal, receive differential input 4 REFCLK+/RCLK+ referenceclock signal 5 REFCLK−/RCLK− reference clock signal 6 CLKREQ# clockrequest signal 7 SWITCH_CTRL_1 the first control signal 8 CLK clocksignal sent by control module 9 CMD command signal sent by controlmodule 10 SWITCH_CTRL_2 the second control signal 11 VDD1 power, 2.7V-3.6 V 12 VDD2 power, 1.7 V-1.95 V 13 VDD3 power, 1.14 V-1.30 V 14DATA3 − DATA0 data signal 15 D1±/D0± data signal 16 RESET# reset signal17 CD# card detection signal

In one embodiment, as shown in FIG. 4, the initial transmission mode ofthe data transmission apparatus 310 which is set to support normaltransmission mode, but is not limited to, it can be set to supporthigh-speed transmission mode too, it is just used to describe thisinvention. First, the control module 304 receives a card detectionsignal CD # and obtains a low level of the card detection signal CD #when the memory card 104 is inserted, the mode selection and switchmodule 306 turns on the power VDD1 and provide power VDD1 to the memorycard 104. The port A in the analog signal switch module 3021 and theanalog signal switch module 3022 are turned on, the card signalselecting module 308 selects a first signal path 315. port A is alsonamed as the first port. More specifically, the mode selection andswitch module 306 send a first control signal SWITCH_CTRL_1 to theanalog signal switch module 3021 and the analog signal switch module3022 to turn on port A, and then, the root complex in the host device102 connects with the control module 304 via the signal path 321 and thesignal path 313. At the same time, the mode selection and switch module306 sends a second control signal SWITCH_CTRL_2 to the card signalselecting module 308 to select the first signal path 315.

Further, the control module 304 sends a clock signal CLK and a commandsignal CMD to the memory card 104, and the memory card 104 returns aresponse signal CMD8 (not shown in FIG. 4) to inform the type of thememory card 104. The control module 304 determines if the memory card104 supports high-speed transmission mode and can be powered by powerVDD3, for example, 1.2 voltage power. Moreover, the level of theresponse signal CMD8 will be low level if the memory card 104 supportsnormal transmission mode, for example, SD card: SD3.X-SD6.X. Thus, thedata transmission apparatus 310 works in the first transmission mode.Otherwise, the level of response signal CMD8 will be high level if thememory card 104 supports high-speed transmission mode, for example, SDcard: SD7.X. In this condition, the control module 304 stops sendingclock signal CLK to the memory card 104 and instructs the mode selectionand switch module 306 to turn on power VDD2 or power VDD3 to power thememory card 104. Moreover, the mode selection and switch module 306sends the first control signal SWITCH_CTRL_1 to the analog signal switchmodule 3021 and the analog signal switch module 3022 to turn off theport A, and the port B (also called the second port) are turned off too.The host device 102 finds signal loss from the PCIE device (not shown inFIG. 4) in the control module 304 via PCIE TX+ signal. The root complexin the host device 102 determines whether the PCIE device was removed orlost. After a while, the host device 102 uninstalls drive software forthe memory card 104 which supports normal transmission mode, and thehost device 102 is reported as hot plug events happened by the rootcomplex. And then, the mode selection and switch module 306 sends thefirst control signal SWITCH_CTRL_1 to the analog signal switch module3021 and the analog signal switch module 3022 to turn on the port B. Itshould be understood by the person having ordinary skill in the art thatthe steps of turning on the port B are not limited to so. It will bedescribed in detail below.

Further, the mode selection and switch module 306 sends the secondcontrol signal SWITCH_CTRL_2 to the card signal selecting module 308,and the card signal selecting module 308 drives a reset signal RESET #to low level. The mode selection and switch module 306 selects the clockrequest signal CLKREQ # and detects if the memory card 104 has enabledCLKREQ # to low level, the card signal selecting module 308 selects thesecond signal path 312 via the second control signal SWITCH_CTRL_2 whenthe level of CLKREQ # is low. While the root complex of the host device102 determines as hot plug events happened and connects with the memorycard 104 via PCIE path (the signal path 321, the signal path 311 and thesignal path 3223). The host device determines that a new PCIE device isinserted and will install Non-Volatile Memory express (NVME) drive. Onthe contrary, the mode selection and switch module 306 selects port Aand the analog signal switch module 3021 and the analog signal switchmodule 3022 turn on port A via the first control signal SWITCH_CTRL_1when the clock request signal CLKREQ # is high level. Meanwhile, theroot complex in the host device 102 connects with the control module 304via signal path 321, port A and the signal path 313, and determines ashot plug events. The host device 102 determines that a new PCIE deviceis inserted and installs drive software which supports normaltransmission mode. And the card signal selecting module 308 selects thefirst signal path 315 via the second control signal SWITCH_CTRL_2, thedata transmission apparatus 310 works in the normal transmission mode,also called in the first transmission mode.

Further, when the data transmission apparatus 310 works in the firsttransmission mode, the control module 304 sends a clock signal CLK and acommand signal ACMD41 (not shown in FIG. 4) to the memory card 104 wherethe command signal ACMD41 is a standard SD card protocol definitioncommand, then the memory card 104 will return a feedback signal whichincludes attribute and drive ability of the memory card 104 afterreceiving the command signal ACMD41, for example, the drive ability ofthe memory card 104 including the memory card 104 supports UHSI mode orUHSII mode, etc.

Specifically, the control module 304 transmits the data signalDATA3-DATA0 and the reference clock signal RCLK± to the memory card 104via the signal path 314, 315 and 3221 when the memory card 104 supportsUHSI mode, for example, the memory card 104 is a SD card SD 3.X.However, the control module 304 transmits the data signal D1±/D0± to thememory card 104 via the signal path 316 and 3223 when the memory card104 supports UHSII mode, and transmits the reference clock signal RCLK±via the signal path 314, 315 and 3221, for example, the memory card 104is one of the SD card SD 4.X-SD6.X.

In another embodiment, the data transmission apparatus 310 works in thefirst transmission mode by default when the memory card 104 is inserted.First, the control module 304 stops sending the clock signal CLK to thememory card 104, and provides power VDD1, power VDD2 or power VDD3 tothe memory card 104. Second, the mode selection and switch module 306sends the first control signal SWITCH_CTRL_1 to the analog signal switchmodule 3021 and the analog signal switch module 3022 to turn off port A,and the port B (also called second port) is turned off too. Finally, thehost device 102 finds signal loss from PCIE device (not shown in FIG. 4)in the control module 304 via PCIE TX± signal. The root complex in thehost device 102 determines that PCIE device was removed or lost. After awhile, the host device 102 uninstalls drive software of the memory cardwhich supports normal transmission mode, and the host device 102 isreported as hot plug events happened by the root complex. And then, themode selection and switch module 306 sends the first control signalSWITCH_CTRL_1 to the analog signal switch module 3021 and the analogsignal switch module 3022 to turn on port B. Also, the mode selectionand switch module 306 sends the second control signal SWITCH_CTRL_2 tothe card signal selecting module 308, and the card signal selectingmodule 308 drives the reset signal RESET # to low level. The modeselection and switch module 306 selects the clock request signal CLKREQ# and detect if the memory card 104 has enabled CLKREQ # to low level,the card signal selecting module 308 selects the second signal path 312to transmit the reference clock signal REFCLK± and the clock requestsignal CLKREQ # via the second control signal SWITCH_CTRL_2 when thelevel of CLKREQ # is low. While the root complex of the host device 102determines as hotplug events happened and connects with the memory card104 via PCIE path (the signal path 321, the signal path 311 and thesignal path 3223). The host device determines that a new PCIE device isinserted and installs a Non-Volatile Memory express (NVME) drive. On thecontrary, if the clock request signal CLKREQ # is high level, the modeselection and switch module 306 selects port A, the analog signal switchmodule 3021, and the analog signal switch module 3022 turn on port A viathe first control signal SWITCH_CTRL_1. Meanwhile, the root complex inthe host device 102 connects with the control module 304 via the signalpath 321, port A and the signal path 313, and the host device 102 isreported as hotplug events happened. The host device 102 determines thata new PCIE device is inserted and installs drive software for the memorycard 104 which supports normal transmission mode. And the card signalselecting module 308 selects the first signal path 315 to transmit thedata signal DATA3-DATA0 and the reference clock signal RCLK± sent fromthe control module 304 via the second control signal SWITCH_CTRL_2, thedata transmission apparatus 310 works in the normal transmission mode,also called in the first transmission mode. As disclosed in thisembodiment, the data transmission apparatus 310 determines the type ofthe memory card 104 according to the level of clock request signalCLKREQ # and performs a mode switch between the first transmission modeand the second transmission mode.

In another embodiment, the data transmission apparatus 310 works in thesecond transmission mode when the memory card satisfies the secondcondition. The control module 304 in the data transmission apparatus 310detects if the memory card 104 is removed or not according to the carddetection signal CD #. Specifically, the host device 102 finds signalloss from PCIE device (not shown in FIG. 4) in the control module 304via PCIE TX± signal. The root complex in the host device 102 determinesthat PCIE device was removed or lost. The mode selection and switchmodule 306 sends the first control signal SWITCH_CTRL_1 to the analogsignal switch module 3021 and the analog signal switch module 3022 toturn off port B, and the port A is turned off too. After a while, theroot complex of the host device 102 determines as hot removal eventshappened, and the host device 102 uninstalls the Non-Volatile Memoryexpress (NVME) drive. The mode selection and switch module 306 selectsport A, the analog signal switch module 3021 and the analog signalswitch module 3022 turns on port A via the first control signalSWITCH_CTRL_1. Meanwhile, the root complex in the host device 102connects with the control module 304 via the signal path 321, port A andthe signal path 313, and the host device is reported as hotplug eventshappened. The host device 102 determines that a new PCIE device isinserted and installs drive software for the memory card 104 whichsupports normal transmission mode. And the card signal selecting module308 selects the first signal path 315 to transmit the data signalDATA3-DATA0 and the reference clock signal RCLK± sent from the controlmodule 304 via the second control signal SWITCH_CTRL_2, and turns offthe power VDD2 or power VDD3.

As embodiment disclosed above, the data transmission apparatus 310 whichworks in the first transmission mode by default or works in the secondtransmission mode by default is not the limitation of this invention.

FIG. 5 shows an example of a mode selection and switch module 306 in thedata transmission apparatus 310 shown in FIG. 3, in accordance with anembodiment of the present invention. As shown in FIG. 5, the modeselection and switch module 306 includes a switch control unit 3062, acommon-mode voltage control unit 3064, a state machine 3066 and a modedetect unit 3068. The switch control unit 3062 is configured to generatea first control signal SWITCH_CTRL_1 to turn on/off port A or port B inthe analog signal switch module 3021 and the analog signal switch module3022 and generates a second control signal SWITCH_CTRL_2 to select thesignal path 312 or the signal path 315.

The common-mode voltage control unit 3064 is configured to outputdifferent common-mode voltage levels according to different kinds ofmemory cards 104. In one embodiment, the data transmission apparatus 310configures a parameter configuration register to set different kinds ofparameters to control the common-mode voltage.

The state machine 3066 is configured to receive external signals andmonitor the state of port A and port B in the analog signal switchmodule 3021, the analog signal switch module 3022 and the situation ofthe switch (not shown in FIG. 4) in the card signal selecting module308. That is, the state machine 3066 records and stores the state of theanalog signal switch module 3021, the analog signal switch module 3022and the card signal selecting module 308, including the state of port A,port B, signal path 312 and signal path 315. The mode detect unit 3068is configured to determine the type of the memory card 104 according tothe response signal CMD8.

FIG. 6 shows a flowchart of an example of a data transmission method 600for providing communication between a host device and a memory card, inaccordance with an embodiment of the present invention. FIG. 6 isdescribed in combination with FIG. 3 and FIG. 4. Although specific stepsare disclosed in FIG. 6, such steps are examples. That is, the presentinvention is well suited to perform various other steps or variations ofthe steps recited in FIG. 6. As shown in FIG. 6, the data transmissionmethod 600 includes steps 601-619 as below:

At step 601: a memory card 104 is inserted into a card slot in the hostdevice 102, for example, SD card SD3.X-SD7.X. The data transmissionapparatus 310 works in a first transmission mode by default.

At step 603: The data transmission apparatus 310 determines the type ofthe memory card 104. The details of steps can refer to the descriptionof FIG. 4. The control module 304 sends a command signal CMD to thememory card 104, and the memory card 104 returns a response signal CMD8to inform the type of the memory card 104. For example, the memory card104 supports a first transmission mode when the level of the responsesignal CMD8 is low level; otherwise, the memory card 104 supports asecond transmission mode.

At step 605: the data transmission apparatus 310 determines if thememory card 104 satisfies the first condition, if it is, performs step613.

At step 607: the mode selection and switch module 306 sends a firstcontrol signal SWITCH_CTRL_1 to the analog signal switch module 3021 andthe analog signal switch module 3022 to turn on the port B if the memorycard 104 satisfies a second condition.

At step 609: the mode selection and switch module 306 sends a secondcontrol signal SWITCH_CTRL_2 to the card signal selecting module 308 toselect a second signal path 312.

At step 611: PCIE paths work, the host device 102 connects with thememory card 104 via signal paths 321, 311, 312, 3221 and 3223. The datatransmission apparatus 310 works in the second transmission mode.

At step 613: The data transmission apparatus 310 satisfies the firsttransmission mode.

At step 615: The data transmission apparatus 310 detects if the memorycard 104 supports UHSII mode, if it is, performs step 619, if not,performs step 617.

At step 617: The data transmission apparatus 310 works in UHSI mode.

At step 619: The data transmission apparatus 310 works in UHSII mode.

Specifically, the data transmission method shown above is performed byeach module in data transmission apparatus 310. The mode selection andswitch module 306 sends a first control signal SWITCH_CTRL_1 to theanalog signal switch module 3021 and the analog signal switch module3022 to turn on port A or port B. Also, the mode selection and switchmodule 306 sends a second control signal SWITCH_CTRL_2 to the cardsignal selecting module 308 to select a first signal path 315 or asecond signal path 312. The first condition includes the memory card 104supports the transmission characters of SD3.X-SD6.X, the firsttransmission mode is called normal transmission mode too; the secondcondition includes the memory card 104 supports the transmissioncharacters of SD7.X, the second transmission mode is called high-speedtransmission mode too.

FIG. 7 shows another flowchart of an example of a data transmissionmethod 700 for providing communication between a host device 102 and amemory card 104, in accordance with an embodiment of the presentinvention. FIG. 7 is described in combination with FIG. 3 and FIG. 4.Although specific steps are disclosed in FIG. 7, such steps areexamples. That is, the present invention is well suited to performvarious other steps or variations of the steps recited in FIG. 7. Asshown in FIG. 7, the data transmission method 700 includes steps 701-723as below.

At step 701: a memory card 104 is inserted into a card slot in the hostdevice 102, for example, SD3.X-SD7.X. The data transmission apparatus310 works in the first transmission mode by default.

At step 703: the analog signal switch module 3021 and the analog signalswitch module 3022 turn off port A according to the first control signalSWITCH_CTRL_1 sent from the mode selection and switch module 306.

At step 705: the mode selection and switch module 306 sends a secondcontrol signal SWITCH_CTRL_2 to the card signal selecting module 308 toselect a first signal path 315, and the card signal selecting module 308drives a reset signal RESET # to low level.

At step 707: the card signal selecting module 308 selects a secondsignal path 312 for transmitting a clock request signal CLKREQ #.

At step 709: the mode selection and switch module 306 detects if thememory card 104 has enabled the clock request signal CLKREQ # to lowlevel. if it is, performs step 713, if not, performs step 711.

At step 711: the level of the clock request signal CLKREQ # is highlevel. The data transmission apparatus 310 determines that the memorycard 104 supports the first transmission mode, or the memory cardsatisfies the first condition. The mode selection and switch module 306sends the first control signal SWITCH_CTRL_1 to the analog signal switchmodule 3021 and the analog signal switch module 3022 to turn on port A,the card signal selecting module 308 selects the first signal path 315via the second control signal SWITCH_CTRL_2.

At step 713: the level of the clock request signal CLKREQ # is lowlevel. The data transmission apparatus 310 determines that the memorycard 104 supports the second transmission mode, or the memory card 104satisfies the second condition. The mode selection and switch module 306sends the first control signal SWITCH_CTRL_1 to the analog signal switchmodule 3021 and the analog signal switch module 3022 to turn on port B.

At step 715: the card signal selecting module 308 selects the secondsignal path 312 for transmitting reference clock signal REFCLK±according to the second control signal. The root complex of the hostdevice 102 determines as hotplug events happened and connects with thememory card 104 via PCIE path (the signal path 321, the signal path 311and the signal path 3223). The host device determines that a new PCIEdevice is inserted and installs Non-Volatile Memory express (NVME)drive.

At step 717: The data transmission apparatus 310 works in the secondtransmission mode, the memory card 104 satisfies the second condition.

At step 719: The data transmission apparatus 310 detects if the memorycard 104 supports UHSII mode, if it is, performs step 723, if not,perform step 721.

At step 721: The data transmission apparatus 310 works in UHSI mode.

At step 723: The data transmission apparatus 310 works in UHSII mode.

FIG. 8 shows another flowchart of an example of a data transmissionmethod 800 for providing communication between a host device 102 and amemory card 104, in accordance with an embodiment of the presentinvention. FIG. 8 is described in combination with FIG. 4. Althoughspecific steps are disclosed in FIG. 8, such steps are examples. Thatis, the present invention is well suited to perform various other stepsor variations of the steps recited in FIG. 8. As shown in FIG. 8, thedata transmission method 800 performed by the data transmissionapparatus 310 includes steps 801-824 as below:

At step 801: the mode selection and switch module 306 in the datatransmission apparatus 310 turns on the power VDD1 and provides powerVDD1 to the memory card 104 when the memory card 104 is inserted intothe host device 102.

At step 802: the control module 304 in the data transmission apparatus310 sends a clock signal CLK to the memory card 104.

At step 803: the control module 304 sends a command signal CMD to thememory card 104. The memory card 104 returns a response signal CMD8 tothe control module 304 after receiving the command signal CMD. Thecontrol module 304 determines the type of the memory card 104, forexample, the memory card 104 satisfies a first condition, e.g.SD3.X-SD6.X; or the memory card 104 satisfies a second condition, e.g.SD7.X.

At step 804: the control module 304 detects if the memory card 104supports high-speed transmission mode. If it is, performs step 805; ifnot, performs step 816.

At step 805: the control module 304 stops sending clock signal CLK tothe memory card 104.

At step 806: the mode selection and switch module 306 detects if thememory card 104 supports power VDD3. If it is, performs step 807; ifnot, performs step 809.

At step 807: the control module 304 detects if the host device 102supports power VDD3, if it is, the mode selection and switch module 306provides power VDD3 to the memory card 104; if not, performs step 809.

At step 808: the mode selection and switch module 306 turns on powerVDD3, performs step 810.

At step 809: the mode selection and switch module 306 provides powerVDD2 to the memory card 104, and performs step 812.

At step 810: the control module 304 gets into a waiting state and waitsfor a predetermined time and performs 813.

At step 811: the mode selection and switch module 306 turns off powerVDD3, performs step 809.

At step 812: the control module 304 gets into a waiting state and waitsfor a predetermined time after the mode selection and switch module 306provides power VDD2 to the memory card 104, performs step 814.

At step 813: the mode selection and switch module 306 detects if thelevel of the clock response signal CLKREQ # returned from the memorycard 104 is low level. if it is, performs step 817; if not, performsstep 811.

At step 814: the mode selection and switch module 306 detects if thelevel of the clock response signal CLKREQ # returned from the memorycard 104 is low level. if it is, performs step 817; if not, performsstep 815.

At step 816: the data transmission apparatus 310 satisfies the firsttransmission mode, the memory card 104 satisfies a first condition.

At step 817: the signal PERSET # which is used to reset the memory card104 is disabled high level effective by the mode selection and switchmodule 306. The data transmission apparatus 310 sends a reference signalREFCLK± to the memory card 104 and performs step 818.

At step 818: the data transmission apparatus detects if the PCIE pathconnects or not, i.e., the second signal path 312 and the signal path311 are selected or not, if it is, performs step 819; if not, performsstep 815.

At step 819: the data transmission apparatus 310 works in the secondtransmission mode, performs step 820.

At step 820: the data transmission apparatus 310 detects if receives acommand to turn off the power VDD2 and/or power VDD3? If it is, performs821; if not, performs 819.

At step 821: the mode selection and switch module 306 turns off powerVDD2 and power VDD3, performs step 802.

At step 822: The data transmission apparatus 310 detects if the memorycard 104 supports UHSII mode, if it is, performs step 824, if not,performs step 823.

At step 823: The data transmission apparatus 310 works in UHSI mode.

At step 824: The data transmission apparatus 310 works in UHSII mode.

It should be understood by the person having ordinary skill in the art,although specific steps are disclosed in FIG. 6, FIG. 7 and FIG. 8, suchsteps are examples. That is, the present invention is well suited toperform various other steps or variations of the steps recited in FIG.6, FIG. 7 and FIG. 8.

Furthermore, the data transmission apparatus 310 includes differentkinds of work states when the memory card 104 is removed, for example,the first work state: the host device 102 shows transmission chip anddevice drive when the data transmission apparatus 310 stands in no-loadcondition; the second work state: the PCIE path is disconnected, i.e.,the root complex in the host device 102 disconnects with the controlmodule 304 and the memory card 104; the third work state: the datatransmission apparatus 310 keeps in the work state before the memorycard 104 is removed. That is, the data transmission apparatus 310 keepsin the first transmission mode if the memory card which is removedsatisfies a first condition, while the root complex in the host device102 keeps connecting with the control module 304. Otherwise, the rootcomplex in the host device 102 keeps connecting with port B and the portB is turned on if the memory card which is removed satisfies a secondcondition, and the data transmission apparatus 310 works in the secondtransmission mode. The work states above mentioned have the shortcomingof time-consuming, and the data transmission apparatus 310 cannot showdevice driver in condition of hot-insertion and removal.

FIG. 9 shows a flowchart of an example of a method for switching signalpath 900, in accordance with an embodiment of the present invention.FIG. 9 shows a flowchart of switching signal path when the datatransmission apparatus 310 stands in no-load condition. FIG. 9 isdescribed in combination with FIG. 4-FIG. 8. As shown in FIG. 9, afterremoving the memory card 104, the method for switching signal pathincludes steps 901-909:

At step 901: the memory card 104 is removed.

At step 903: the data transmission apparatus 310 determines the workstate of the data transmission apparatus 310 before the memory card 104is removed, and detects if the data transmission apparatus 310 works ina first transmission mode, if it is, performs step 909; if not, performsstep 905.

At step 905: port B in an analog signal switch module 3021 and an analogsignal switch module 3022 keep turning on.

At step 907: wait, the root complex in the host device 102 willdisconnect with port B after a while.

At step 909: the root complex in the host device 102 connects withcontrol module 304, and the analog signal switch module 3021 and theanalog signal switch module 3022 turn on port A.

The data transmission apparatus 310 saves time of install and/oruninstall time of drive software for the memory card 104 when the datatransmission apparatus 310 is triggered by memory card 104 inserting, inaccordance with an embodiment of the present invention.

While the foregoing description and drawings represent embodiments ofthe present invention, it will be understood that various additions,modifications and substitutions may be made therein without departingfrom the spirit and scope of the principles of the present invention asdefined in the accompanying claims. One skilled in the art willappreciate that the invention may be used with many modifications ofform, structure, arrangement, proportions, materials, elements, andcomponents and otherwise, used in the practice of the invention, whichis particularly adapted to specific environments and operativerequirements without departing from the principles of the presentinvention. The presently disclosed embodiments are therefore to beconsidered in all respects as illustrative and not restrictive, thescope of the invention being indicated by the appended claims and theirlegal equivalents, and not limited to the foregoing description.

Unless otherwise expressly indicated herein, all numerical valuesindicating mechanical/thermal properties, compositional percentages,dimensions and/or tolerances, or other characteristics are to beunderstood as modified by the word “about” or “approximately” indescribing the scope of the present disclosure. This modification isdesired for various reasons including industrial practice, material,manufacturing, and assembly tolerances, and testing capability.

As used herein, the phrase at least one of A, B, and C should beconstrued to mean a logical (A OR B OR C), using a non-exclusive logicalOR, and should not be construed to mean “at least one of A, at least oneof B, and at least one of C.”

In this application, the term “controller” and/or “module” may refer to,be part of, or include: an Application Specific Integrated Circuit(ASIC); a digital, analog, or mixed analog/digital discrete circuit; adigital, analog, or mixed analog/digital integrated circuit; acombinational logic circuit; a field programmable gate array (FPGA); aprocessor circuit (shared, dedicated, or group) that executes code; amemory circuit (shared, dedicated, or group) that stores code executedby the processor circuit; other suitable hardware components (e.g., opamp circuit integrator as part of the heat flux data module) thatprovide the described functionality; or a combination of some or all ofthe above, such as in a system-on-chip.

The term memory is a subset of the term computer-readable medium. Theterm computer-readable medium, as used herein, does not encompasstransitory electrical or electromagnetic signals propagating through amedium (such as on a carrier wave); the term computer-readable mediummay therefore be considered tangible and non-transitory. Non-limitingexamples of a non-transitory, tangible computer-readable medium arenonvolatile memory circuits (such as a flash memory circuit, an erasableprogrammable read-only memory circuit, or a mask read-only circuit),volatile memory circuits (such as a static random access memory circuitor a dynamic random access memory circuit), magnetic storage media (suchas an analog or digital magnetic tape or a hard disk drive), and opticalstorage media (such as a CD, a DVD, or a Blu-ray Disc).

The apparatuses and methods described in this application may bepartially or fully implemented by a special purpose computer created byconfiguring a general-purpose computer to execute one or more particularfunctions embodied in computer programs. The functional blocks,flowchart components, and other elements described above serve assoftware specifications, which can be translated into the computerprograms by the routine work of a skilled technician or programmer.

The description of the disclosure is merely exemplary in nature and,thus, variations that do not depart from the substance of the disclosureare intended to be within the scope of the disclosure. Such variationsare not to be regarded as a departure from the spirit and scope of thedisclosure.

What is claimed is:
 1. A data transmission apparatus providescommunication between a memory card and a host device, said datatransmission apparatus comprising: a first port connects to a controlmodule in said data transmission apparatus, is selected by a firstcontrol signal; a second port connects a card signal selecting module insaid data transmission apparatus, is selected by said first controlsignal; a first signal path connects to said control module and saidcard signal selecting module, said data transmission apparatusimplements signal transmission between said control module and said cardsignal selecting module via said first signal path, wherein a secondcontrol signal is used to select said first signal path; and a secondsignal path connects to said host device and said card signal selectingmodule, said host device transmits signal to said card signal selectingmodule via said second signal path, wherein said second control signalis used to select said second signal path, when said memory cardsatisfies a first condition, said first control signal selects saidfirst port and said second control signal selects said first signalpath, said data transmission apparatus connects said host device andsaid memory card via said first port and said first signal path, andworks in a first transmission mode, when said memory card satisfies asecond condition, said first control signal selects said second port andsaid second control signal selects said second signal path, said datatransmission apparatus connects said host device and said memory cardvia said second port and said second signal path, and works in a secondtransmission mode.
 2. The data transmission apparatus of claim 1,wherein said data transmission apparatus further comprising: a modeselection and switch module, is configured to generate said firstcontrol signal and said second control signal according to said memorycard; and a couple of analog signal switch modules, which comprise saidfirst port and said second port.
 3. The data transmission apparatus ofclaim 2, wherein said mode selection and switch module furthercomprising: a switch control unit, is configured to generate said firstcontrol signal and said second control signal; a voltage control unit,is configured to output different common mode voltage; a state machine,is configured to receive signal transmitted in said data transmissionapparatus; and a mode detect unit, is configured to detect types of saidmemory card.
 4. The data transmission apparatus of claim 1, wherein saidcontrol module is configured to determine the type of said memory cardaccording to a response signal from said memory card, and determine ifsaid memory card satisfies said first condition or said secondcondition.
 5. The data transmission apparatus of claim 1, wherein saidhost device communicates with said control module when said first portis selected, and said host device communicates sub-signal with saidmemory card via said second signal path when said second port isselected, and said host device communicates TX signal and RX signal withsaid memory card via a third signal path.
 6. The data transmissionapparatus of claim 1, wherein said card signal selecting module connectswith said memory card via a fourth signal path, is configured to selectsaid first signal path or said second signal path according to saidsecond control signal; and said first signal path connects to saidfourth signal path to transmit data signals, a reset signal and areference clock signal when said memory card satisfies said firstcondition, and said second signal path connects to said fourth signalpath to transmit a reference clock signal and a clock request signalwhen said memory card satisfies said second condition.
 7. The datatransmission apparatus of claim 4, wherein said control module furtherreceives a card detection signal sent from said memory card and detectsif said memory card is inserted or not.
 8. The data transmissionapparatus of claim 1, wherein said first condition includes said memorycard satisfies transmission characteristic of SD3.X, SD4.X, SD5.X orSD6.X; and said second condition includes said memory card satisfiestransmission characteristic of SD7.X.
 9. The data transmission apparatusof claim 1, when said memory card satisfies the first condition, saiddata transmission apparatus works in UHSII mode if said memory cardsupports UHSII mode, if not, said data transmission apparatus works inUHSI transmission mode, wherein said UHSII mode and said UHSI mode areboth first transmission mode.
 10. A data transmission method forproviding communication between a host device and a memory card,comprising: a data transmission apparatus generates a first controlsignal to make said host device connects to said data transmissionapparatus; said data transmission apparatus generates a second controlsignal to make said data transmission apparatus connects to said memorycard; when said memory card satisfies a first condition, said firstcontrol signal selects a first port and said second control signalselects a first signal path, said data transmission apparatus connectssaid host device and said memory card via said first port and said firstsignal path, and works in a first transmission mode, when said memorycard satisfies a second condition, said first control signal selects asecond port and said second control signal selects said second signalpath, said data transmission apparatus connects said host device andsaid memory card via said second port and said second signal path, andworks in a second transmission mode.
 11. The data transmission method ofclaim 10, further comprising: a control module in said data transmissionapparatus receives a response signal from said memory card, anddetermines if said memory card satisfies said first condition or saidsecond condition, and determines the type of said memory card.
 12. Thedata transmission method of claim 10, wherein said data transmissionapparatus transmits data signals, a reset signal and a reference clocksignal to said memory card via said first signal path, said host devicetransmits a reference clock signal and a clock request signal via saidsecond signal path, and said host device transmits TX signal and RXsignal to said memory card via a third signal path, wherein said thirdsignal path belongs to a peripheral component interconnect express(PCIE) bus.
 13. The data transmission method of claim 11, furthercomprising: said control module receives a card detection signal anddetects if said memory card is inserted or not.
 14. The datatransmission method of claim 10, a mode selection and switch module insaid data transmission apparatus selects said first port via said firstcontrol signal, selects said first signal path via said second controlsignal and drives a reset signal to low level.
 15. The data transmissionmethod of claim 14, wherein said mode selection and switch modulefurther detects the level of a clock request signal, and detects ifselects said second signal path according to said clock request signal.16. The data transmission method of claim 15, further comprising: saiddata transmission apparatus determines that said memory card satisfiessaid first condition when said clock request signal equals to a highlevel, if not, said memory card satisfies said second condition.
 17. Thedata transmission method of claim 10, when said memory card satisfiesthe first condition, said data transmission apparatus works in UHSIImode if said memory card supports UHSII mode, if not, said datatransmission apparatus works in UHSI transmission mode, wherein saidUHSII mode and said UHSI mode are both first transmission mode.
 18. Adata transmission system includes a host device, a data transmissionapparatus, and a memory card, comprising: a first control signal isconfigured to control a signal path between said host device and saiddata transmission apparatus; a second control signal is configured tocontrol another signal path between said data transmission apparatus andsaid memory card; and when said memory card satisfies the firstcondition, said first control signal selects a first port and saidsecond control signal selects a first signal path, said datatransmission apparatus connects said host device and said memory cardvia said first port and said first signal path, and works in a firsttransmission mode, when said memory card satisfies the second condition,said first control signal selects a second port and said second controlsignal selects a second signal path, said data transmission apparatusconnects said host device and said memory card via said second port andsaid second signal path, and works in a second transmission mode.
 19. Amethod for switching signal path in said data transmission system ofclaim 18, when said memory card is removed from data transmissionsystem, comprising: said data transmission apparatus keeps selectingsaid first port if said memory card which is removed satisfies saidfirst condition, and said host device connects with a control module insaid data transmission apparatus; and said data transmission apparatuskeeps selecting said second port if said memory card which is removedsatisfies said second condition, and will break connection with saidsecond port after a period of time, and then selects said first port.